1. Field of the Invention
The invention relates to a matrix print head with several armature device groups, where each armature device group comprises a magnet yoke with an electromagnetic coil, disposed on one of the arms of the magnet yoke, and an armature, where the armature serves as a drive for a print element, and wherein the armature can be positioned in a fast sequence against the pole surfaces of the magnet yoke and back into a rest position.
2. Brief Description of the Background of the Invention Including Prior Art
The actuation of such matrix print heads results in a wear at the pole faces and at the bearing positions of the armature. The lifetime of the matrix print heads is consequently limited based on this wear.
It has been attempted in the past to decrease the wear at the pole faces by employing a plastic foil. The plastic foil, however, generates an additional air gap, which decreases the efficiency of the magnet system.
A lubricating device for the print wires in dot matrix print heads is known from the German Utility Model DE-Gbm 73 00 743. This reference teaches to furnish one of the halves of the casing with a recess into which an oil-impregnated felt is inserted. The print wires are furnished with oil and thus the friction is decreased.